Alternate flow control for fluid streams



Dec. 3, 1957 R. H. BRAUNLICH ,3

ALTERNATE FLOW CONTROL FOR FLUID STREAMS Filed Feb. 8. 1954 UnitedStates Patent Ofiice 2,815,033 Patented Dec. 3, 1957 ALTERNATE FLOWCONTROL FOR FLUID STREAMS Richard H. Braunlich, West Chester, Pa.,assignor to American Viscose Corporation, Philadelphia, Pa., acorporation of Delaware Application February 8, 1954, Serial No. 408,637

4 Claims. (Cl. 1377) This invention relates to the spinning ofartificial textile fibers and, more particularly, to a novel method andapparatus for providing sharp interfaces between variously colored areasin the spinning solution prior to extrusion through the spinnerct.

A serious disadvantage arising in all previously known methods andapparatus for injecting a colored dope or spinning solution into a mainspinning solution stream has been the inability to cut 01? the colorsolution sharply to avoid a more or less continuous coloring of the mainstream. The present invention provides a method and apparatus whichcontrols with great accuracy the precise amount of secondary fluid thatis injected into the main stream.

While the present invention will be described in conjunction with theconventional spinning of viscose filaments, it will be understood thatit may be used with any other type of synthetic fiber such as, forexample, nylon or cellulose acetate.

The primary object of the present invention therefore is to provide anapparatus for injecting a secondary stream of viscose into a primaryviscose stream so that the flow of primary viscose may be substantiallyinterrupted by the secondary viscose solution.

A further object of the invention is to provide apparatus forinstantaneously cutting oil the supply of a secondary viscose stream asinjected into a main viscose stream.

A further object of the invention is to provide a method for completelyand instantaneously stopping the flow of a secondary viscose stream whencombined with a primary stream.

A still further object of the invention is to provide apparatus forsubstituting one for the other different streams of viscose in acontinuously flowing viscose spinning apparatus.

Further objects will be apparent from the specification and drawings inwhich:

Figure 1 is a transverse sectional view of a viscose spinning machineincorporating the present invention;

Figure 2 is an enlarged fragmentary sectional detail which is a part ofthe structure of Figure 1;

Figure 3 is an enlarged transverse section of the injection nozzleassembly used in conjunction with the present apparatus;

Figure 4 is a fragmentary detail as seen generally at IV-IV of Figure 3;and

Figure 5 illustrates a variety of results that may be achieved in theviscose stream as it progresses from the injection nozzle to and throughthe rounder.

The invention comprises essentially the provision of an injectionorifice or nozzle which is located in the viscose conduit between thecandle filter and the spinneret. Throughout the present specification,the viscose solution which is added to the main stream will be referredto as the secondary viscose which is usually of a different color orcomposition than the main viscose stream. Strictly speaking, the presentapparatus and method do not necessarily deal with an injection procedurein the sense that a small quantity of secondary fluid is substantiallycontinuously injected into a main stream. The present inventioncontemplates a more or less complete substitution of one viscose streamfor the other, thus providing alternate sections or segments in acontinuous stream having sharp interfaces between the segments. In orderto accomplish the initial complete interruption of the so-called mainstream, I provide an aligned injection orifice which is capable ofdischarging a volume of secondary fluid sufficient to completely fill ametered bore in the main fluid conduit. The shape and relative size ofthe two conduits together with the shape of the injection chamber enablea complete or partial shutting off of the main viscose stream to beaccomplished. When it is desired to reintroduce the primary stream intothe rounder or spinneret passage, I not only shut off the supply of thesecondary or colored viscose but I positively prevent any additionalsecondary fluid from passing through the injection nozzle either in theform of seepage or in larger amounts. This is accomplished by a sharpreduction in the pressure on the injection fluid which has the ellect ofreversing the flow of the fluid in the secondary line between thesecondary pump and the nozzle. Such reversal does not have to be morethan enough to prevent seepage from the nozzle but, of course, shouldnot be sufiicient to withdraw primary viscose back into the secondaryconduit or pump.

Referring now to the drawings, the primary stream of viscose is suppliedthrough a conventional conduit or pipe 10 and bracket 11 to pump 12which is driven by spur gears 13 and 14 from shaft 15. This apparatus aswell as the candle filter bracket 16 and shaft 17 is mounted on thespinning machine frame 18 as is well known in the art. The primaryviscose then is pumped through a candle filter 20 from whence it passesthrough my improved injection nozzle 21, rounder 22 and spinneret 23.Filaments 24 are coagulated in the conventional bath 25 in accordancewith standard practice. The secondary viscose stream which is ordinarilyof a diflerent color than the primary stream is pumped from a reservoiror other supply 30 through conduit 31 by means of a pump 32. In thepresent instance, I have shown pump 32 as being manually operated, butit will be understood that a mechanical drive for the secondary pumpwhich provides the desired reciprocating motion may be used. From pump32, the secondary stream passes through conduit 33 and thence into thenozzle 21.

In order to provide a sharp cut-off for the main viscose stream, Iintroduce the main stream from the candle filter 20 into the nozzle body21a (Figure 3) through the counterbored and tapped opening 34. The mainviscose stream then passes through a plurality of passages 35, 35 whichdesirably have a reduced bore 36 at the opposite end of the body 21a.These passages are, in the preferred form, drilled concentrically aroundthe centerline of the body. The nozzle housing 21b connects with therounder 22 by means of a threaded boss 37 and has a single centralpassage or conduit 33 through which all the viscose travels to thespinneret 23. The housing 21b is connected to the body 210 by means of athreaded connection, and axial adjustment of the position of the body inthe housing can be achieved by varying the thickness of the gasket 39which is compressed between the end of the body 21a and a counterboredshoulder in the housing. The upstream end of conduit 38 terminates in aconical chamber 40 which tapers or converges from a diameter slightlygreater than the diametric distance between opposite orifices 36, 36 tothe diameter of conduit 38. Thus it will be apparent that the primarystream of fluid, such as viscose, is introduced to chamber 40 throughpassages 35, 35 and orifices 36 and is discharged from chamber 40through conduit 38. The secondary fluid is introduced into the body 21athrough a tapped passage 41 which communicates with the secondaryinjection orifice 42 through suitably drilled passages 43 and 44. Thediameter of orifice 42 is selected in view of the pressure on thesecondary stream so that sufiicient secondary fluid is injected into thechamber 40 at its apex. In the present instance, 1 have shown the boreof orifice 42 as being substantially the same diameter as the bore ofconduit 38. However, this relation may be varied depending upon therelative pressures in the primary and secondary streams and the spacingfrom the tip of orifice 42 to the inner terminus of conduit 38.

The pump 32 for injecting or supplying the secondary viscose stream isof standard design but is operated so that pressure is periodicallyapplied to the secondary stream and then quickly removed by a reversalof the pump direction. When this pressure sequence is accomplishedmanually, the pump is driven through lever 45 which has a ratchet andpawl connection with the pump gears. Assuming that a counterclockwiseturning of ratchet 46 (Figure 2) applies pressure to the secondarystream, a counterclockwise turning of lever 45 through a predeterminedarc drives ratchet wheel 46 through pawl 47 which is spring-loaded at48. In order to relieve the injection pressure on the secondary stream,the lever 45 is reversed for all or a part of its forward stroke. Bydcpressing the thumb latch 49 in the handle of the lever, the pawl 50 israised to disengage the teeth of the ratchet wheel 46. If the pawl 50 isinitially raised and retained in a raised position, no clockwisemovement of the ratchet wheel 46 occurs. On the other hand, the ratchetmay be completely reversed through its forward are by releasing thethumb latch 49, thus permitting the pawl 50 to engage the teeth of theratchet wheel under urging of spring 51.

In accordance with the degree or amount of reversal of the pump 32, itis possible to shut ott sharply the flow of secondary viscose throughorifice 42. On the forward or injection stroke of pump 32, the secondaryviscose passes from orifice 42 into chamber 40 and conduit 38. Thiscontinues during the forward or pressure stroke of lever 45 and pump 32.At the end of the pressure stroke, a reversal of pump 32 immediatelydraws back the secondary viscose in orifice 42 and passages 43 and 44together with some of the primary viscose in chamber 40. The primaryfluid then immediately passes into conduit 38 and flow of this fluid isresumed through orifices 36, 36. This provides sharp interfaces in thestream of viscose V (Figure 5) which is fed through the rounder 22 andinto spinneret 23. Various types of injection are illustrated in Figure5 in which the viscose segment 60 completely fills conduit 38 and theremainder of the fluid passage to the spinneret. In this case, however,the friction between the walls of the conduit and the segment of coloredor different viscose tends to drag the skin of the seg ment so that anextremely sharp cut-oil will not ordinarily be obtained due to thetrailing or stringing out eflect which is partially illustrated. If,however, the injection is not sufiiciently severe to completely fillconduit 38, then a colored viscose segment 61 is produced. In this form,there will be limited distortion due to the decreased velocity near thewalls of the conduit out a substantially sharp interface is stillentirely possible. In the injection of segment 62, however, maximumsharpness is possible because the injected viscose segment or materialremains near the center of the main viscose stream so that the axialvelocity throughout the segment is substantially equal. This latter formprovides the maximum sharpness of cut-oft for the above reason.Furthermore, to enhance the sharpness of the cut-off, it is desirable toplace the injection nozzle 21 as near the spinneret 23 as possible, andit will be understood that the nozzle 21 may be located directly in backof the spinneret 23 ahead of the rounder or the rounder as such may beeliminated entirely.

The magnitude of the reversal of pump 32 depends on the variousoperating conditions and the result desired.

The frequency of the occurrence of the secondary stream segments as wellas the main stream segments is, of course, dependent upon the frequencyof actuation of pump 32. It is important to note, however, thatregardless of the spacing between the two individual stream segments inthe rounder 22 it is possible to provide, for all practical purposes, nomixing of the streams. The secondary viscose stream is in etfeet choppedinto segments of various length and then injected into the main streamto form a final stream of viscose that is extruded through a spinneret.In this way it is possible to achieve much more interesting and novelcolor efiects in the spun yarn. There is an absence of color blendingwhich, with proper spacing, can be made highly effective by way ofcontrast.

Having thus described my invention, I claim:

1. A method of combining independent liquid streams by intermittentlyintroducing each stream into a common conduit which comprises the stepsof applying pressure to a first liquid supply to form a continuous firststream, injecting the first stream through the conduit, applyingpressure to a second liquid within a supply line to form a second streamunder a greater pressure than the first stream, injecting the secondstream through the conduit, said second stream injection momentarilyinterrupting the passage of the first stream through the conduit,discontinuing the second stream to permit the first stream to resume itspassage through the conduit, and reducing the pressure within the supplyline for the second stream to withdraw a portion of the first streamwithin said supply line to prevent seepage of the second stream into thefirst stream passing through the chamber and conduit.

2. A method of combining independent liquid streams by intermittentlyintroducing each stream into a common conduit which comprises the stepsof applying pressure to a first liquid supply to form a continuous firststream, injecting the stream into a chamber leading to the conduit toflood the chamber, further injecting the stream through the conduit,applying pressure to a second liquid within a supply line to form asecond stream under a greater pressure than the first stream, injectingthe second stream directly through the flooded chamber into the conduit,said second stream injection momentarily interrupting the passage of thefirst stream through the conduit, continuing the flow of the firststream within the chamber, discontinuing the second stream to permit thefirst stream to resume its passage through the conduit, and reducing thepressure within the supply line for the second stream to withdraw aportion of the first stream within the supply line to prevent seepage ofthe second stream into the first stream passing through the chamber andconduit.

3. The method according to claim 2 wherein the first and second streamscomprise a. clear viscose stream and a colored viscose streamrespectively.

4. The method according to claim 2 wherein the first and second streamscomprise diflerently colored viscose streams.

References Cited in the file of this patent UNITED STATES PATENTS866,112 Foster Sept. 17, 1907 976,148 Caps Nov. 22, 1910 1,613,000Widdowson Jan. 4, 1927 1,955,825 Palmer Apr. 24, 1934 1,975,153 JacquetOct. 2, 1934 2,007,871 Oldham July 9, 1935 2,313,060 Friedman Mar. 9,1943 2,421,475 Beeh lune 3, 1947 2,500,816 Grid Mar. 14, 1950 2,506,415Geflroy May 2, 1950 2,598,066 Morse May 27, 1952 2,621,596 Jacuzzi Dec.16, 1952 2,650,168 Dijk Aug. 25, 1953 FOREIGN PATENTS 517,897 France of1921

